Description: Flat incrustations, several mm in thickness and several square cm in lateral expansion, with very characteristic star-shaped oscules and canal system. These star-shaped systems are isolated from each other by a cm at least of flat featureless surface (H. caerulea-close up). Slimy-smooth when touched. The consistency is toughish, not very compressible.
Color: Light purple.
Habitat: Encrust dead areas of reefs and walls.
Distribution: Occasional Florida, Bahamas and Caribbean.
Kingdom Animalia Phylum Porifera Genus Halisarca Species Halisarca caerulea